HIV-1 entry inhibitors targeting Phe43 cavity in gp120

描述（由申请人提供）：两个最近解析的HIV-1 gp 120与CD 4和人中和抗体17 b的Fab片段复合的X射线晶体结构提供了CD 4和gp 120之间相互作用的结构细节，并揭示了在gp 120中存在大的疏水空腔，其中CD 4的Phe 43结合（Phe 43空腔）。该项目的目的是使用基于结构的方法来鉴定小分子先导化合物，这些化合物将结合到该空腔以阻断CD 4-gp 120相互作用并阻止HIV-1进入宿主细胞。该方案的具体目的如下：（1）通过大数据库的虚拟筛选，鉴定对接到gp 120中的CD 4结合腔（Phe 43腔）中的小分子。自动化分子对接技术将被用作虚拟筛选工具，以仅选择那些适合空腔并与gp 120中的CD 4结合位点相互作用的化合物。(2)通过免疫学和病毒学筛选试验，鉴定阻断gp 120与CD 4结合的HIV-1进入抑制剂。将通过两步过程选择潜在的先导化合物进行进一步研究：（a）通过高通量酶联免疫吸附测定（ELISA）来测定从虚拟筛选中选择的化合物，以鉴定结合gp 120并阻断gp 120与CD 4结合的抑制剂，和（B）进一步筛选从（a）中选择的抑制剂对HIV-1介导的细胞融合和细胞病变效应（CPE）的抑制活性，以及体外细胞毒性。(3)优化先导化合物以产生有效的抗HIV-1药物。最好的先导化合物将进一步优化，通过设计的重点库和结构活性分析（SAR）。总体而言，该项目将产生新的先导化合物作为潜在的HIV-1进入抑制剂。本课题的长期目标是通过化学合成和结构活性分析对先导化合物进行优化，筛选出3-4个最佳化合物作为新型抗HIV-1化疗药物进行进一步的临床前研究。

DESCRIPTION (provided by applicant): Two recently solved x-ray crystal structures of HIV-1 gp120 complexed with CD4 and the Fab fragment of a human neutralizing antibody 17b provided structural details of the interactions between CD4 and gp120 and revealed the presence of a large hydrophobic cavity in gp120 where Phe43 of CD4 binds (Phe43 cavity). The objective of this project is to use a structure-based approach to identify small molecular lead compounds that will bind to this cavity to block the CD4-gp120 interaction and prevent HIV-1 entry to host cells. The specific aims of this proposal are as follows: (1) To identify, by virtual screening of large databases, small molecules that dock into the CD4 binding cavity (Phe43 cavity) in gp120. The automated molecular docking technique will be used as a virtual screening tool to select only those compounds that fit into the cavity and interact with the CD4 binding site in gp120. (2) To identify, by immunological and virological screening assays, lead HIV-1 entry inhibitors that block gp120 binding to CD4. The potential lead compounds will be selected by a two-step process for further studies: (a) the selected compounds from virtual screening will be assayed by high throughput enzyme-linked immunosorbent assays (ELISA) to identify inhibitors that bind to gp120 and block gp120 binding to CD4, and (b) the selected inhibitors from (a) will be further screened for inhibitory activity against HIV-1 mediated cell fusion and cytopathic effects (CPE), and for in vitro cytotoxicity. (3) To optimize lead compounds for generating potent anti-HIV-1 agents. The best lead compounds will be optimized further through design of focused libraries and structure-activity analysis (SAR). Overall, this project will yield new lead compounds acting as potential HIV-1 entry inhibitors. The long-term goal of this proposal is to optimize the lead compounds through chemical synthesis and structure activity analyses and select 3-4 best compounds for further preclinical studies as novel ianti-HIV-1 chemotherapeutic agents.